This invention relates to support devices and in particular a support for protective devices used as guard rails, scaffolding, or the like.
Guard rails, hand rails, scaffolding, and the like are protective and supportive devices used around work areas, in connection with construction, and in protecting workers from dangerous machinery and other dangerous situations. In many instances such guard rail devices are temporary in nature, intended to be used only during periods of construction or installation of machinery. On other occasions, such guard rails are more permanent, meant to remain in place for long periods of time. In terms of the overall discussion of scaffolding, guard rails, and the like, it is to be understood herein that the term "stanchion" may refer generically to either vertically upright or horizontal members used in guard rails, scaffolding, and the like.
At the heart of any efficient stanchion, it is desirable to provide ones which are easily installable, may be used for long periods of time (even permanently), and, where desired, may be easily removed.
The disposition of guard rails around the perimeter of work areas has long been used and many arrangements have been suggested. The most common type of guard rail is often improvised and jerry-built. Recently, however, governmental agencies at various levels have begun to specify safety precautions along most work and building sites. Amongst these provisions is the Federal Goverment's Occupational Health and Safety Act (OHSA), which specifies not only the height of guard rails, but their rigidity and general configuration. Much of the present guard rails are not in conformance with these regulations or are too expensive for economical use.
One suggested guard rail was disclosed by Lionetto in U.S. Pat. No. 3,662,993. That device calls for stanchions which are wedged between upper and lower floors. The difficulty with a design such as this is that, in the first place, it requires an opposed upper floor. Secondly, the use of two bearing surfaces requires an uneconomical combination of parts in order to secure the railings to the site. Thirdly, the protective device cannot be left permanently on the site. Furthermore, it is doubtful that such a device would be absolutely secure, particularly if the opposed floors are uneven or if the screw jack combination is not sufficient to provide uniform and continuous pressures.
Still another suggested type of guard rail was provided by Melfi in U.S. Pat. No. 3,351,311. In this arrangement, there is provided a C-clamp for surrounding and engaging a cement floor. However, such a device tends to pivot about the point of engagement (that is, at the contact of the C-clamp with the floor). In addition, variation in floor sizes may require different size C-shaped clamped for practical engagement, thereby rendering such an arrangement complicated and expensive in use.
One other suggested means of engaging a post in a rail, or a rail in a floor, was disclosed by Macrea in U.S. Pat. No. 406,657. Macrea provides an end of a rail having two sleeves pivotally mounted for expansion within a frusto-conically-shaped cavity in a post. For this device to work, however, the cavity had to be especially designed with its special shape, and the grip of the rail would not be believed to be too secure, in any event. So that if such a post and rail combination were used with the railing taking the form of a stanchion, and having to support a guard rail, it would be weak and insecure.
All of the suggested devices herein, and other similar devices, are believed to be either permanent or of temporary design. None have the flexibility to be used as both permanent or temporary installations. This lack of flexibility adds to their cost and inconvenience of use.
In the past, brackets for supporting railings have been rigidly secured to stanchions. Thus, McCarthy in U.S. Pat. No. 791,713 shows a typically rigid, rail-holding brackets which are integral with the stanchion. This means that if the stanchion must be partially removed (so as to admit equipment to a work area, for example) the railings will have to be removed from the stanchion before removing the stanchion itself. This problem is further compounded where the stanchion is removed by rotation. A rigid bracket will obviously rotate with the stanchion thereby necessitating the removal of the railings.
Bettis, in U.S. Pat. No. 57,073 suggests brackets which are held in place by a wedge. Removal of the wedge, however, would necessarily result in the bracket dropping down the stanchion making more difficult removal of the stanchion. Williams, in U.S. Pat. No. 1,864,159 suggests a guard rail in which the brackets are rings held to the post by set screws. A loosening of the set screws would necessarily result in the dropping of the bracket thereby making removal of the rail more difficult.